Rack type bread cooler



Dec. 8, 1964 A. J. FERRO 3,160,261

RACK TYPE BREAD COOLER Original Filed May 9. 1960 10 Sheets-Sheet 1 FIG. I

"k INVENTOR.

ANTHONY J. FERRO Dec. 8, 1964 A. J. FERRO 3,160,261

RACK TYPE BREAD COOLER Original Filed May 9. 1960 v 10 Sheets-Sheet 2 I0 N N m Kl .2 INVENTOR. ANTHONY J. FERRO Dec. 8, 1964 A. J. FERRO RACK TYPE BREAD COOLER l0 Sheets-Sheet 3 Original Filed May 9, 1960 FIG. 4

INVENTOR.

ANTHONY J. FERRO haw/w Dec. 8, 1964 A. J. FERRO 3,160,261

RACK TYPE BREAD COOLER Original Filed May 9, 1960 10 Sheets-Sheet 4 INVENTOR ANTHONY J. FERRO BY M/ w Dec. 8, 1964 A. J. FERRO 3,

RACK TYPE BREAD COOLER Original Filed May 9, 1960 10 Sheets-Sheet 5 F ill L! INVENTOR. ANTHONY JQFERRO 1381- 8, 1964 A. .1. FERRO RACK TYPE BREAD COOLER Original' Filed May 9. 1960 10 Sheets-Sheet 6 OQI,

INVENTOR.

ANTHONY J. FERRO flfi%m%v Dec. 8, 1964 A. J. FERRO RACK TYPE BREAD COOLER 1O Sheets-Sheet '7 Original Filed May 9, 1960 INVENTOR.

ANTHONY J. FERRO flaw 4% Dec. 8, 1964 A. J. FERRO RACK TYPE BREAD COOLER l0 Sheets-Sheet 8 Original Filed May 9, 1960 FIG. H

INVENTOR.

ANTHONY J. FERRO flfi%mzv Dec. 6, 1964 A J FERRO 3,160,261

RACK TYPE BREAD COOLER Original Filed May 9, 1960 10 Sheets-Sheet 9 FIG. I2

INVENTOR.

ANTHONY J. FERRO 3,16tl,261 RACK TYPE BREAD (IGGLER Anthony .l'. Ferro, York, Fa, assignor, by mesne assignments, to Baker Ferhins, lino, New York, FLY a corporation of New York Continuation of application Ser. No. 127,690, May 9, 1960.

This application duly 23, 1963, No. 297,997 1t) Elairns. (6C5. 1%85) This invention relates to a rack conveying system and more particularly to a rack conveying system for a bread cooler in which a plurality of multi-shelved racks are movable in a closed loop through a cooling chamber, and in which means is provided along one run of the closed rack conducting loop for loading rows of hot freshly baked loaves of bread onto successive rack shelves and for urloading rows of cooled loaves of bread from successive rack shelves.

The closed rack conducting loop includes upper and lower tracks pendently supporting and along which contiguous racks are adapted to be pushed; elevating means for engaging and raising successive racks through a loading and unloading station and releasing them on the uppertracks to push the row of contiguous racks ahead; and lowering means for engaging and lowering successive racks and releasing them on the lower tracks to push the row of contiguous racks ahead. At the loading and unloading station there is provided an infeed or loading conveyor for introducing rows of hot bread; a discharge or unloading conveyor for carrying away rows of cooled bread; a loading pusher for transferring successive rows of hot bread from the infeed conveyor onto successive shelves of the racks; and an unloading pusher for transferring successive rows of cooled bread from successive rack shelves onto the discharge conveyor.

An important feature and object of the invention is to provide improved apparatus of the type described above constructed and arranged to simultaneously load and unload not only two successive shelves of individual racks but also the bottom shelf of one rack and the top shelf of a succeeding rack.

Another object is to provide elevating means and operating means therefor for intermittently raising successive racks through the loading and unloading station a shelf space at a time to permit simultaneously loading and unloading of two successive shelves, and rack advancing means and operating means therefor moving a succeeding rack into position to be engaged by the rack elevating means so that the succeeding rack is moved through the loading and unloading station with its top shelf spaced one shelf space from the bottom shelf of a preceding rack. A related object is to provide simple and eificient control means for correlating the advancement of a rack to the elevating means with the raising of a preceding rack by the elevating means.

Another object of the invention is to provide an apparatus of the type described including means for stabilizing the racks against swinging movement as they are transferred from the lower tracks of the closed rack conducting loop to the upper tracks thereof and as they are transferred from the upper tracks of the closed rack conducting loop to the lower tracks thereof.

Other objects and advantages reside in certain novel features of construction, arrangement and combination United States Patent 0 of parts which will be hereinafter more fully described, reference being had to the accompanying drawings showing an exemplary embodiment of the invention. Referring to the drawings:

FEGURES l and 1A are longitudinal vertical sectional views through contiguous portions of a bread cooler housing with the various elements contained therein shown more or less diagrammatically;

FlGURE 2 is a view in elevation on an enlarged scale of the rack-elevating means and the means for advancing racks to the base of the elevating means taken adjacent one side of the cooler housing on the line 22 of FIGURE 1;

FIGURE 3 is a sectional view on an enlarged scale taken on the line 33 of FIGURE 2;

FIGURE 4 is a sectional View on an enlarged scale taken on the line 4-4 of FIGURE 3;

FIGURE 5 is a view in elevation of the rack lowering means and associated rack stabilizing means taken adjacent one side of the cooler housing on the line 55 of FIGURE lA;

FIGURE 6 is a sectional view taken on line 6-6 of FIGURE 5;

FIGURE 10 is an end elevation of the unloading pusher taken on line Ill-10 of FIGURE 9;

FIGURE 11 is an enlarged view taken on line 11-1l of FIGURE 1 at the near side of the cooler;

FIGURE 12 is a view in side elevation at the lower forward end of the cooler taken from the near side as viewed in FIGURE 1 showing the timing means for various elements of the cooler;

FIGURE 13 is a view of the rack elevating timing drum taken on line 13-13 of FIGURE 12;

FIGURE 14 is a view in side elevation of the bread loading and unloading conveyors for the cooler; and

FIGURE 15 is a diagram of the electrical control system.

Referring particularly to FIGURES 1 and 1A, the rack type break cooler comprises a generally rectangular elongated housing lt) defining a bread cooling chamber it through which racks 12, carrying loaves of bread to be cooled, travel in an elongated closed loop having an upper horizontal run 13 and a lower horizontal run 14.

The housing It is preferably formed of sheet metal panels supported by suitable skeleton framework, and may be provided with access doors and observation windows, all of which is conventional and therefore is not illustrated or described in detail. The racks may be of any suitable form, being in the nature of an open rectangular framework constructed of metal angles, plates, tubing or the like, preferably of aluminum arranged to support a plurality of horizontal, vertically spaced grids forming shelves, six in the present instance, for supporting hot loaves of baked bread. Certain details of the racks will be adverted to later in the description as the necessity arises.

The forward end of the cooling chamber 11 is arranged to provide a loading and unloading station 15, at which station successive rows of bread loaves to be cooled are loaded onto the racks 12 and successive rows of bread loaves that have been cooled are unloaded from the shelves of the racks 12. Elevating means, indicated as a whole by reference numeral 16 raises successive racks 12 through the loading and unloading station from the lower horizontal run 14 to the upper horizontal run 13.

A pair of horizontal, vertically spaced conveyors extend transversely of the coolerhousing and project through a suitable opening, not shown, in a near side wall thereof into the loading and unloading station 15 between the rack elevating means 16 and the front wall 17 of the cooler housing 10, so that the shelves of the racks 12 can be successively brought into; register with the conveyors as the racks 12 are elevated through the loading and unloading station 15. These conveyors may be of any suitable type for conveyance of bread loaves as, for example, slat conveyors, as best shown in FIGURE 14. The upper conveyor 18, hereinafter referred to as the loading conveyor, conveys the bread loaves into. the cooler to a position in front of a rack being elevated by the elevating means 16, where pusher means, hereinafter referred to as the loading pusher 19, pushes successive rows of bread loaves from the loading conveyor 18 onto sucessive shelves of a rack 12 as it is intermittently elevated through the loading and unloading station 15. The lower conveyor 20, hereinafter referred to as the unloading conveyor, is adapted to convey cooled bread loaves from the cooler, successive rows of cooled bread loaves being pushed from successive shelves of a rack 12 in the loading and unloading station 15 onto the unloading conveyor 20 by pusher means, hereinafter referred to as the unloading pusher z l. a

For the purpose of orienting various elements of the cooler, the sides thereof will be referred to throughout the description as the near and far sides when viewing the cooler as shown in FIGURES 1 and 1A.

RACKS The racks '12 are all identical in construction, so that in describing any one particular rack it will be understood that the other racks are similarly constructed. Referring particularly to FIGURE 1, rack 12a is shown as having six shelves, the shelves being designated by the reference numeral-s 23 to 28. While, for purpose of illustration, the racks 12 are shown with six shelves and the operation of the apparatus is described hereinafter in respect of racks with six shelves, it will become apparent that the apparatus is equally adapted to handle racks with a lesser or greater number of shelves.

Each of the racks 12 has a plate welded or otherwise secured across the upper portion of its opposite ends. In FIGURE 1, a plate 30 is shown on one end of the rack 12a, it being understood that a similar plate is provided on the opposite end thereof, and that all the racks 12 are similarly provided with plates 311. Extending from the face of each of the plates 30, laterally outward of the racks 12, is a stub shaft 31, as best shown in FIG- URES 2 and 3. The shafts 31 are disposed above the center of gravity of the racks 12 and located centrally between the front and rear sides of the racks; The outer ends of the shafts 31 are engaged by the elevating means 16 in transporting successive racks from lower run 14 to upper run 13; and are also engaged by lowering means, designated as a whole by the reference numeral 32, in transporting successive racks from upper run 13 to lower run 14, as will be hereinafter described in detail.

Each of the shafts 31 is provided approximately midway between its ends, as best shown in FIGURE 2, with a roller. 33. The rollers 33 engage longitudinally extending tracks disposed along the upper and lower runs 13 and 14. Referring particular ly to FIGURES 1, 2 and 3, I

there is shown an upper track 35 and a lower track 36 supported, respectively, on a series of upper and lower brackets 37 and 38 secured to and extending inwardly from inner and outer upright frames 39 and 40, respectively, at one side of the cooler structure. The spaced inner and outer frames 39 and 40 at each side of the cooler are each formed by a plurality of vertical and longitudinally extending angle frame members and throughout the description the frame members forming the inner frames are referred to collectively as inner frame 39 and the frame members forming the outer frames are referred to collectively as outer frame 40. It is understood that a similar upper and lower track and supporting construction is provided at the opposite side of the cooler structure, whereby the tracks 35 and 36 provide guide supports along which the rollers 33 at opposite ends of the racks 12 are adapted to roll in moving the racks 12 along the upper and lower runs 13 and 14.

ELEVATING MEANS As explained above, elevating means 16 raises the racks 12 from the lower run 14 to the upper run 13 through the loading and unloading station 15. The elevating means 16 includes a pair of endless chains 41 disposed in parallel vertical laterally spaced planes sufficiently far apart to receive a rack 12 therebetween.

FIGURES 2 and 3 show a chain 41 on one side of the cooler which is trained around sprockets 43, 44 and 45 and a shoe 46, it being understood that sprockets can be substituted for the shoe 46 if desired. The chain 41 carries three equidistantly spaced lugs 47, 4S and 49 adapted to engage the shaft 31 of the racks 12 for moving them in the manner to be described. This chain, sprocket and shoe arrangement is duplicated at the op posite side of the cooler.

The sprockets 43, 44, 45 and the shoes 46 are so disposed that the chains 41 trained thereover provide in the elevating means 16, a vertical ascending run 50 for raising succcessive racks 12 through the loading and unloading station 15 between the unloading pusher 21 on one side and the loading pusher 19, the loading conveyor 18 and the unloading conveyor 20 on the other side; a horizontal rearwardly traveling run 51' for moving successive racks 12 from the loading and unloading station 15 onto the end of the upper tracks 35; and an irregular return run 52 over the sprockets 43 and 44 and back to the sprocket 45.

Again considering just one side of the cooler, with reference particularly to FIGURES 2 and 3', the sprocket 43 is keyed on a travsverse through shaft 53 journaled in a bearing 54, mounted on a longitudinally extending frame member of inner frame 39. Sprocket 44 is keyed on a short transverse shaft 57, the shaft 57 being journaled in suitable bearings 56 and 58 mounted, respectively, on inner and outer frames 39"and 40. Sprocket'45, for a reason which will become apparent, is mounted on a short transverse shaft 61 for relative rotation with respect thereto, as by a roller bearing 42, best shown in FIGURE 4. The transverse shaft 61 is journaled in suitable bearings 34 and 62, mounted on inner and outer frames 39 and 40. It is understood that a similar arrangement of shafts, bearings and supports is provided at the opposite side of the cooler.

It will be noted that the sprockets 43 and 44 are disposed at an elevation above the sprocket 45 and the reason therefor will bellater explained.

Referring to FIGURE 1, it will be seen that thedepth d of a rack 12 is considerably greater than the height it between two successive shelves of a rack. For example, the depth d of a rack may be 17% inches to accommodate bread loaves of maximum length, while the height dbetween shelves may be 8 inches to accommodatebread loaves of maximum height. Thus, in order to move a rack a horizontal distance rearwardly along the shoes 46 so that its lowermost front edge will clear the uppermost rear edge of the succeeding rack, the distance between the lugs 47, 43 and 49 must be equal at least to the distance between the top and bottom shelves of a rack, which in the case of a six shelf rack would be (hXS) or 40 inches plus the depth d of a rack or 17% inches, making a total of 57 /2 inches. Actually this distance may be reduced somewhat, for example to 55 inches, since the rack will move a horizontal distance of about 2 /2 inches as it moves upwardly about the radius of the curved forward ends 65 of the shoes 46.

With the lugs 47, i8 and 49 spaced as described above, it is apparent that as they move the racks through the load ing and unloading station 15, any two successive shelves of a rack will register with the loading and unloading conveyors 18 and 28, these conveyors being spaced apart the same distance, 8 inches, as the shelves of a rack, so that the two shelves can be simultaneously loaded and unloaded. However, this lug arrangement will not move a rack into position to bring its top shelf in register with the unloading conveyor 20 when the bottom shelf of a preceding rack is in register with the loading conveyor 13. I have, therefore, provided a construction and arrangement of elements whereby, when the bottom shelf of a rack registers with the loading conveyor 13, the succeeding rack is moved independently of the elevating means 16 to a position bringing its top shelf in register with the unloading conveyor 2-0, so that not only are two successive shelves of a rack simultaneously loaded and unloaded, but also the bottom shelf of one rack and the top shelf of a succeeding rack. The means for accomplishing this will be described later in the description.

As shown in FIGURES l and 3, rack 12:: is being raised through the loading and unloading station 15 by reason of engagement of its shafts 31 by the lugs 43 of the chains 41. On reaching the top of the run 59, the rack 12a will be pushed along run 51 onto tracks 35 where it will engage arid push rack 12b ahead of it and consequently all the racks 12 in upper run 13 will be pushed along the upper tracks 35. When rack 12:: reaches the position occupied by rack 12!; in FIGURES l and 3, it will remain there by reason of disengagement of lugs -28 from the shafts 31 of rack 12a as the lugs 48 move to the return run 52.

The means for operating the elevating means 16 includ'es a motor Ml disposed in the lower forward portion of the cooler and mounted in any suitable manner on the framework at one side of the cooler. Motor M1 drives a longitudinally extending torque tube '72 journaied in suitable bearings carried-by the cooler framework. The drive connection includes a chain "I'd trained around sprockets 75 and '76 on the motor output shaft and the torque tube 72. The forward end of the torque tube 72 is connected by a flexible coupling "77 with the input shaft of a speed reducing unit 78. To complete the drive to the elevating means 16, a chain '79 is trained around a sprocket 80 (FIGURE 1) on the output shaft of the speed reducing unit 753 and a sprocket 31 (FIGURE 2) on the through shaft 53 of the elevating means 16.

Referring particularly to FIGURES 1 and 3, a guide plate 82 is provided along the inside of the ascending run 50 of the chain 41 forming a vertical continuation of the shoe 46 and terminating at its lower end adjacent the periphery of sprocket 45. Another vertical guide 84 is disposed forward of and in spaced relation with respect to the ascending run 59 of the chain 41 and is arranged to be engaged by the roller 33 of an ascending rack 12. The upperportion of a rack as it'ascends through the-loading and unloading zone is thus stabilized or restrained from rearward and forward movement by reason of engagement of chain 41 with guide 82 and engagement of roller 33 with guide 8 As best shown FEGURE 3, the lower portion 35 of guide 8% curves rearwardly to merge with lower track 36, While the upper portion 5% follows the contour of the shoe 46 and extends rearwardly over the forward end portion of upper track 35. Similar guide plates for the chain 41 and rack roller 33 are pro vided at the opposite side of the elevating means i6.

LOADER PUSHER Referring particularly to FIGURES 1, 7 and 8, the pusher 19 includes a rectangular frame 88 comprising a pair of laterally spaced, longitudinally extending tubular frame members 89 connected together at their forward ends by a transversely extending tubular frame member 91. Secured to a pair of longitudinally spaced vertical outer frame members 4% at each side of the cooler are brackets 92. Each of the brackets 92 is provided at the inner side thereof with a pair of vertically spaced concave rollers 93 and each of the longitudinally extending tubular frame members 89 is mounted between two pairs of rollers 93 so that the pusher frame 88 is adapted to be retained between the rollers 93 and movable longitudinally therealong. A pusher or ram 94 is pendently supported from transverse pusher frame member 91 and, as best seen in FIGURES 1 and 7, is adapted to sweep across the loading conveyor 18 to push a row of bread loaves from the loading conveyor 18 onto the shelf 28 of the rack 312a.

In order to impart reciprocating longitudinal movement to the pusher for pushing successive rows of bread loaves from the loading conveyor 18 onto successive rack shelves, the frame members 39 are provided midway of their ends with upstanding posts 95. On each side of the cooler a transversely extending jack shaft 96 is rotatably mounted in bearings 9'7 supported on a bracket 98 extending between and secured to a pair of inner vertical frame members 39. Mounted on the outer end of each of the jack shafts 96 between inner and outer frame members 39 and 4b is a counterweighted crank 99. Connecting rods 1% provide a pivotal connection between each of the cranks 99 and a respective post 95. Thus, as the cranks 99 turn through from the position shown in FIGURE 7, the pusher 19 is retracted to move a row of bread loaves from the loading conveyor 18 onto the shelf ofa rack, and as the cranks 99 continue to turn through another-180 back to their original positions, the pusher 19 is advanced to its original position in readiness for moving another row of bread loaves. Rotation is imparted to the cranks 99 through sprocket chains 101 trained over sprockets Hi2, which sprockets are secured to the inner ends of the jack shafts 96.

The drive for the sprocket chains 101 from motor M2 will be described in more detail hereinafter in connection -with the drive for the unloading pusher 21, since motor M2 operates both loading pusher 19 and unloading pusher 21.

UNLOADING PUSHER Referring particularly to FIGURES 1, 9 and 10, the unloading pusher 21 includes a rectangular frame 103 comprising a pair of laterally spaced, longitudinally extending tubular frame members 104 connected at their forward ends by a transversely extending pusher element M5. Secured to and extending upwardly fromthe rearward end of each of the frame members 104 is a saddle block 1%. A transversely extending rod 107 is rotatably mounted in the saddle blocks 1% and projects laterally therebeyond, terminating between inner and outer vertical frame members 39 and 40 of the cooler. Each of the tubular frame members 104 of the unloading pusher frame 163 is received between pairs of fore and aft concave rollers 198 pendently supported in suitable manner from frame members of the cooler, whereby the pusher frame 193 is movable longitudinally. v

In order to impart reciprocating longitudinal movement to the unloading pusher for pushing rows of bread loaves from successive shelves of racks 12 onto the unloading conveyor 25 there is provided a transversely extending through shaft 109 journal-ed at its ends in bearings 13% supported on brackets 111 which are secured to inner vertical frame members 39 of the cooler. Mounted on the projecting outer ends of through shaft 189 are counterweighted cranks 112. Connecting rods 113 are secured at one end to opposite ends of the transversely extending rod 197 of the pusher frame 103, and are pivotally connected at their opposite end with the cranks 112 Thus, as the cranks 112 turn through 180 from the position shown in FIGURES 1 and 9, the pusher 31 is moved to extended position to move a row ofbread loaves from the shelf of a rack onto the unloading conveyor 20, and as the cranks 112 continue to turn through another 180 back to their original positions, the pusher 21 is retracted to its original position in readiness for moving another row of bread loaves from a succeeding rack shelf.

Rotation is imparted to the cranks 112 through sprocket chains 101 trained over sprockets 114, which sprockets are secured to the through shaft 109. As previously stated, the motor, M2, which is mounted at one side of the cooler, operates both the unloading pusher 21 and the loading pusher 19. To accomplish this, one of the sprocket chains 1111 is trained over a sprocket 115 on the motor shaft, one of the sprockets 114 of the unloading pusher 21 and one of the sprockets 1112 of the loading pusher 19. Since shaft 109 is a through shaft, the other sprocket chain 101 at the opposite side of the cooler, is

also driven.

RACK LQWERING MEANS As previously stated lowering means 32 lowers the racks 12 from the upper run 13 to the lower run 14. Referring particularly to FIGURES 1A, and 6, the rack lowering means includes a pair of endless chains 12f! di posed in parallel vertical laterally spaced planes sufficiently far apart to receive a rack 12 therebetween. In FIGURES 1A, 5 and 6, one of the chains 12%) at one side of the cooler is shown, and referring thereto, the chain 120 is trained around drive sprocket 121, upper shoe 122, upper sprocket 123, lower sprocket 124 and lower shoe 125. The sprockets 123 and 12 1 are fixed on the inner ends of the short shafts 126 and 127, journaled in bearings 128 supported in suitable manner by inner and outer vertical frame members 33 and at This chain, sprocket and shoe arrangement is duplicated on the opposite side of the cooler.

The sprockets 121 are fixed on a through shaft 123, journaled at its ends in suitable bearings, not shown, carried by the side frame members of the cooler. Thus by rotating through shaft 12?, as later. described, both chains 120 are driven. The described sprocket, shoe and chain arrangement provides in the lowering means 32, a horizontal upper run 130 for moving successive racks rearwardly from the rearward end of upper tracks 35; a vertical descending run 131 for lowering successive racks to the lower tracks 36; a. horizontal lower run 132 for moving successive racks forwardly along lower tracks 36; and a return run 133.

The chains 12!) are each provided with three equidistantly spaced outwardly projecting lugs 134-, 135 and 136 adapted to engage the outer end portions of the rack stub shafts 31 topush successive racks rearwardly along upper run 130. The means for, supporting the racks 12 along the descending run 131 will be described with reference to one of the chains 120, it being understood that the other of the chains 120 is provided with similar means. Pivotally mounted to the chain 126 ahead of each of the lugs 134, 135 and 136 are triangular latch members 137, 138 and 139. Referring to latch member 138, FIGURE 6, pivotal movement thereof is limited by reason of engagement of an extension of chain pin 14% in slot 141 of latch member 138. It is understood that a similar arrangement is provided for the latch members 137 and 139.

A guide plate 142 is provided along the descending run 131 of the chain 120 at the inner side thereof. Another guide plate 143 is. provided along the descending run 131 of the chain 126 at the outer side thereof and spaced therefrom to form a channel 144 adapted to receive the rack rollers 33, the lugs 134, 135 and 136 of, the chain 12th and the latches 137, 133 and 139. The rack rollers 33 are arranged to engage the outer guide plate 143, which together with inner. guide plate 142 for the chain stabilizes the upper portions of the racks against fore and aft movement as the racks supported on the latch members 137, 138 and 139 descend along the run 131.

The racks 12 are thus delivered to the lower run 14, being supported on the lower tracks 36 by engagement therewith of the rack rollers 33. By reason of engagement of the chain lugs 134, or 136 with the rack stub shafts 31, successive racks are pushed ahead and consequently all'the racks on lower run 14 are pushed ahead one rack space. Referring particularly to FIGURE 1A. when rack 12!? has been pushed ahead to the position shown occupied by rack 120, the lug 135 disengages rack stub shaft 3-1 and travels along return run 133.

The chains 12% of the lowering means 32 are driven from the torque tube 72 through a flexible coupling 145 and speed reducer 146. To complete the drive, a chain 147 is trained around a sprocket 148 on the output shaft of the speed. reducer 146 and a sprocket 149 on the through shaft 129 of the lowering means 32. Since both the elevating means 16 and the lowering means 32 are driven from the motor M1, it will be apparent that they are operated in synchronism.

.RAPID RACK ADVANCE CONVEYOR For the reasons previously stated, in the description of the rack elevating means 16, means independent of the chains 41 of the rack elevating means 16 is provided, to move a terminal rack, rack 12z in FIGURE 1, from lower tracks 36 to a position wherein its stop shelf 23z is in alinernent with unloading conveyor 23 when the bottom shelf 28 of rack 12a is in alinement with loading conveyor 18, so that shelves 232 and 28 can be simultaneously unloaded and loaded.

This means is in the form of a conveyor 150, and referring to FIGURES l and 3, includes an endless chain 151 extending along the forward end portion of lower run 14 above the level of the lower track 36 at the near side of the cooler. Endless chain 151 is trained around tandem arranged sprockets 152 and 153. The rear sprocket 152 is fixed on the inner end of a short shaft 151which, as best shown in FIGURE 2, is journaled in bearings carried by inner and outer vertical frame members 39 and 4t 1 The front sprocket 153 is keyed on the inner end of the short shaft 61 adjacent sprocket 45, as best shown in FIGURES 2, 4 and 11. The chain 151 is provided with a pair of diametrically opposite outwardly projecting lugs 155 and 156 arranged to engage the rack stub shafts 31 for advancing successive racks as brought out above. While not shown, it will be understood that a similar arrangement of sprockets, shafts and chain is provided at the far side of the cooler.

The chains 151 are arranged to operate at a more rapid rate of speed than the chains 41 of the elevating means 16, such differential in speed being permitted by reason of the sprockets 45 of the elevating means 16 being freely mounted on the shafts 61, as previously stated in the description of the elevating means.

The rack advance conveyor 150 is driven from motor M4 which, referring to FIGURE 1, is mounted on the far side of the cooler. A transversely extending through shaft 157 is mounted in the lower forward end of the cooler, being journaled at its ends in suitable bearings (not shown) carried by inner and outer frames 39 and 49. Through shaft 157 is driven from motor M4- through sprocket chain 153 trained around sprocket 159 on motor shaft 160 and sprocket 161 on through shaft 157, the said sprockets and chain all being disposed on the far side of the cooler. On each end of the shaft 157 there 162 and a respective sprocket 163 fixed on theshort shafts 61 is a sprocket chain 164, whereby rotation is transmitted j to the shafts 61 from through shaft 157 for operating 9 the rack advance conveyor The operation of the rack advance conveyor 15b is synchronized with the operation of the elevating means 16 through the means hereinafter described with reference to the electrical control system shown in FIGURE 15.

INFEED AND DISCHARGE CONVEYORS As previously stated, the infeed and discharge conveyors are preferably in the form of endless slat conveyo rs 18 and 20, which may be constructed in any suitable manner as shown, for example, in Patent No. 2,643,- 421, granted August 11, 1953 to C; M. Vitz. As shown in FIGURE 14, the conveyors 18 and 2% extend at one end around respective shafts 165 and 166 journaled in suitable bearings carried by the outer frame 419 at the near side of the cooler. At their opposite ends, conveyors 1S and 2t? extend around respective drive shafts 167 and 168. The conveyor drive shafts 167 and 16% extend between and are journaled at their ends in suitable bearings carried by the inner end portions of spaced bearing plates 1619 and 1711. The bearing plates 169 and 171 span and are suitably secured to inner and outer frames 39 and 4d) at the far side of the cooler, and extend inwardly of the cooler.

The conveyor driving shafts 167 and 163 are operated through gear reducer 171 from the motor M3 by a sprocket chain 172 trained over sprocket 173 on gear reducer output shaft 174, idler sprocket 175, sprocket 1'75 fixed on shaft 167 and sprocket 1176 fixed on shaft 168.

The control means for intermittently operating the infeed and discharge conveyors 18 and 2% in timed relation with the other elements of the cooler, includes a disc 177 fixed on the output shaft of a speed reducer 173 which is mounted on top of the plate members 16?, 1.7%. A sprocket chain 178 trained over a sprocket 179 on the driving shaft 167 and a sprocket 18% on the input shaft of speed reducer 178 effects rotation of cam disc 177 in timed relation with operation of the infeed and discharge conveyors 18 and 2h. The speed reduction to the disc 177 is such as to rotate the same through one revolution for a linear travel of the infeed and discharge conveyors 18 and through a distance suficient to introduce a row of hot loaves into the cooler and to discharge a row of cooled loaves from the cooler. A limit switch LS3 controlling operation of motor M3 is arranged to be engaged by a lug 186 on the disc 177. The functioning of the control means is described hereinafter in detail in connection with the electrical diagram, FTGURE l5.

ELEVATING TIMING DRUM In order to provide for controlied intermittent movement of the racks 12 through the loading and unloading zone 15, referring particularly to FIGURES 1, l2 and 13, a drum 181 is mounted on shaft 132 for rotation therewith. The shaft 182 is mounted in the lower forward end of the cooler, being journaled in suitable bearings carried by the inner and outer frames 39 -md 4t? at the near side of the cooler. A sprocket chain 183 trained over a sprocket 184 fixed to the shaft 57 of the elevating means 16 and over a sprocket 185 fixed on drum shaft 182 provides for rotation of the drum 182 in timed relation with the elevating of racks through the loading and unloading zone 15 by the elevating means 16. Further details of the timing drum 131 together with its function will be brought out hereinafter in describing the operation of the cooler with reference to the electrical diagram.

RACK ADVANCE TIMING DISC In order to control the operation of the rack advance conveyor 1513 to stop a rack when its top shelf is in register with the discharge conveyor 21?, referring particularly to FIGURES 1, 11 and 12, a timing disc 187 is mounted on shaft 188 for rotation therewith. The shaft 138 is mounted in the lower forward end of the cooler, being journaled in suitable bearings carried by the inner and outer frames 39 and 443 at the near side of the cooler.

RACK STABILTZING MEANS Disposed at the near side of the cooler, as .best shown in FTGURES l, 11 and 12, between inner frame 39 and the near end of a rack as it is elevated from lower run 14 to upper run 13, is a vertically extending guide channel 192, U-shaped in cross section, with the open side of the U-shaped channel facing the rack being elevated. The lower portion of the guide channel 192 curves rearwardly terminating in anopen end in horizontal alignment with a lug 193 projecting laterally outward from the lower leading end of a rack 12 when said rack is on lower run 14. Thus as a rack, for example rack 1232, in FIGURE 1, moves to the position shown occupied by rack 122:, its lug 193 is received in guide channel 192, and as the rack is elevated to the position shown occupied by rack 12a, engagement of lug 193 in the guide channel 192 stabilizes the lower end of the rack, preventing fore and aft swinging movement thereof. As previously stated, the upper end portion of a rack 12 is stabilized as it is elevated from lower run 14 to upper run 13 by guide plates 82 and 84, between which the elevating chain 41 and rack roller 33 is received. The upper open end of the guide channel 192 is disposed so that the lug 193 rides out of the channel 192 as the rack approaches its upper limit of travel, whereupon the rack is free to be moved rearwardly along upper run 13. I

In order to stabi ize the lower end of a rack as it is advanced by the rack advance conveyor 1513 from the position shown occupied by rack 12y to the position shown occupied by rack 12x, one of the two lugs 19d of chain conveyor 195 is arranged to engage a rack lug 193 to move the lower end of the rack in synchronism with movement of the upper end of the rack by reason of engagement of one of the lugs 155, 156 of conveyor 156 with a rack stub shaft 31. Chain conveyor 1% is trained around tandem arranged sprockets 1% and 197 mounted on respective shafts 19S and 199 journaled in suitable bearings carried by the cooler framework. Shaft 199 is driven from shaft 157, which as previously described also operates the rack advance conveyor 151 through a sprocket chain 211? trained over sprockets 211 and 212 mounted respectively on shafts 199 and 157.

V Disposed at the near side of the cooler, as best shown in FlGURE-S 1A, 5 and 6, between inner frame 39 and the near end of a rack as it is lowered from upper run 13 to lower run 14, is a vertically extending guide channel 213, U-shaped in cross section, with the open side of the a U-shaped channel facing the rack being lowered. The

upper portion of the guide channel 213 curves rearwardly terminating in an open end in horizontal alignment with a rack lug 193 of a rack on upper run 13. Thus as a rack, for example rack 12m in FIGURE 1A, moves rearwardly to the descending run 131 of the lowering means 32, its

lug 193 is received in guide channel 213, and as the rack' is lowered to the position shown occupied by rack 12m,

engagement of lug 193 in the guide channel 213 stabilizes the lower end of the rack, preventing fore and aft swinging movement thereof. As previously described, the upper end portion of a rack 12 is stabilized as it is lowered from upper run 13 to lower run 14 by guide plates 142 and 143, between which the chain 121D of the lowering means 32 and the rack roller 33 is received. The lower open end of guide channel 213 is disposed so that the rack lug 1% rides out of the channel 213 as the rack approaches its lower limit of travel, whereupon the rack is free to be moved forwardly along lower run 14. The guide channel 213 is interrupted intermediate its length to permit passage of the rack stub shafts 31 as a rack is moved forward from the position shown occupied by rack 1212 to the position shown occupied byrack 120.

In order to stabilize the lower end of a rack as the rack is moved along the horizontal upper run 1349 of rack lowering means 32, the lug 214 of chain conveyor 215 is arranged to engage a rack lug 193 to move the lower end of the rack in synchronism with movement of the upper end of the rack by reason of engagement of one of. the lugs 134, 135, 136 of chain conveyor 12% with a rack stub shaft 31. Chain conveyor 215 is trained around tandem arranged sprockets 216 and 217 mounted on respective shafts 218 and 219 journaled in suitable bearings carried by the cooler framework. Shaft 219 is driven from shaft 127 of the lowering means 32 through a sprocket chain 220 trained over sprockets 222i and 222 mounted respectively on shafts 127 and 219.

OPERATION The operation of the cooler will now be described with particular reference to FIGURES 1, 1A and the electrical diagram, FIGURE 15. As shown in the drawings, for purpose of illustration, there are twenty-eight racks with six shelves to a rack, or a total of 168 shelves. Assuming again, for purpose of illustration only, a cooling time of 90 minutes, then a cycle of events, as hereinafter described, must occur approximately every 32 seconds,

which cycle is controlled by the timer T.

Assuming the racks in the position shown, in which a cycle of events controlled by the timer T is about to begin, then when start push button 2% is' pressed, a circuit is completed to energize control relay CR1. Energization of control relay CR1 closes its normally open contact CRl-Cl to provide a holding circuit to retain control relay CR1 energized upon release of start push button 209. Contact CRll-Cl remains closed until the circuit to control relay CR1 is broken by pressing stop push button 232. Energization of control relay CR1 also closes a second normally open contact CRfi-CZ.

Upon closing of contact CR1C2, a circuit is completed to the motor TM of timer T and to solenoid operated timer clutch TCL thereby closing contact TCL-C. With the various elements of the apparatus in the relative positions shown in FIGURE 1, let it be assumed that the timer T is approaching the end of the 32 second period for which it has been set.

When timer T times out, it momentarily opens normally closed timer switch contact T 8-1, thereby breaking the circuit and stopping timer motor TM. However, the timer T does not reset at this time since the timer clutch TCL remains energized. As the same time, normally open timer switch contact TS-2 momentarily closes which, as seen in FIGURE 15, completes a circuit to loading and unloading pusher motor starter MHT, whereupon the loading pusher 19 and unloading pusher'ZSl operate to respectively load a row of hot loaves of bread from infeed conveyor 18 onto the bottom shelf 28 of rack 12a, and unload a row of cooled loaves from the top shelf 232 of rack 122 onto discharge conveyor 26?.

Energization of pusher motor starter MZ-ST also opens a contact MZ-ST-Cl in the circuit to the starter Ml-ST of the motor M1 for the rack elevating means 16 and rack lowering means 32, and the circuit to the starter MS-ST of the motor M3 for the inteed conveyor 18 and discharge conveyor 20, to insure against starting of the elevating means, the lowering means, the infeed conveyor and the discharge conveyor While the loading and unloading pushers are operating.

Initial movement of the unloading pusher 21 releases limit switch LS2 as shown in FIGURES 1 and 9, whereupon, referring again to FIGURE 15, contact 182431 of limit switch LS2 opens and contact LSZ-CZ closes. Closing of contact LSZ-CZ completes a circuit to energize control relay CRS which closes its normally open contact CRS-Cl to maintain the circuit to the pusher motor starter MZ-ST when the momentarily closed timer switch contact TS-2 re-opens. Energization of control relay CR5 also closes its normally open contact CR5C3.

Closing of contact CRS-C3 completes a circuit to and energizes control relay CR6 which effectsclosing of its normally open contacts CRfi-CZ and CR6-C3, and opening of its normally closed contact-s CR6C1 and CR6-C4. With contact CR6C1 now open and with LS2-C1 now also open, as explained above, timer motor TM and timer clutch TCL are both de-energized, whereupon-the timer is reset. Closing of contact CR6-C2 prepares the circuit to the motor starter Ml-ST for the elevating and switch LS2, whereupon its contact LSZ-Cl re-closes andits contact LSZ-CZ re-opens. Re-closing of contact LSZ-Cl again energizes the timer motor TM and the timer clutch TCL, whereupon timer T starts timing. Since contacts LS2-C2 and CR6-C4 are now open, the circuit to pusher motor starter M2ST is broken, so that the loading and unloading pushers 19 and 21 remain at rest in the positions as shown in FIGURE 1. Re-opening of contact LSZ-CZ, it will be seen, again de-energizes control relay CR5, so that its contacts CRS-Cl and CR5-C3 re-open. Also, de-energization of pusher motor starter MZ-ST causes its contact MZ-ST-Cl to re-close.

Since contact LSZ-Cl, contact M2ST-C1 and contact CR6C2 are now all closed, a circuit is completed to motor starter Ml-ST for operating the rack elevating means 16 and the rack lowering means 32, and a circuit is also completed to motor starter M3-ST for operating the infeed and discharge conveyors 18 and 2h. Energization of motor starters M1-ST and Mfr-ST opens their normally closed contacts Ml-ST-Cl and MS-ST-Cl, to insure against operation of the loading and unloading pushers 19 and 21 while the rack elevating and lowering means 16 and 32 and the infeed and discharge conveyors 18 and 20 are operating. Normally open contact M1-ST-C2 is closed upon energization of motor starter Ml-ST, the significance of which is brought out later in the description.

Operation of motor M3 also operates the cam disc 177, FIGURE 14, as previously described, the speedreductio-n being such so as to rotate the cam disc 177 through one revolution while the infeed and discharge conveyors 18 and 2% travel a linear distance to cause the infeed conveyor 18 to introduce a row of hot loaves of bread into the cooler in position to be later pushed onto the shelf of a rack by the loading pusher 19, and to remove a row of cooled loads from the cooler deposited on the discharge conveyor 20 by the unloading pusher 27..

Upon initiation of operation of the infeed and discharge conveyors 18 and 2th by motor M3, cam disc 1'77 disengages limit switch LS3, FIGURE 14, causing its contact LS3-C1, FIGURE 15, to open and its contact LS3-C2 to close. Closing of contact LS3-C2 completes a circuit to and energizes control relay CR3. Energization or" control relay CR3 closes its normally open contacts CR3C1 and CR3-C2, thereby completing a circuit to and energizing control relay CR4. Energization of control relay CR4 opens its normally closed contacts CRd-Cl and CR-CZ and closes its normally open contact CPA-C3.

As above set forth, the circuit to: the motor starter.

Ml-ST is completed simultaneously with the circuit to motor starter Mlv-ST to simultaneously initiate operation or" the rack elevating and lowering means 16 and 32 and the infeed and discharge conveyors 18 and 20. As previously described, upon operation of the rack elevating means 16, timing drum 181 is rotated through sprockets 184 and 185 and sprocket chain 183, FIGURES 1, 12 and 13, the sprocketsbeing proportioned to eifect rota tion of timing drum 181 through one revolution in the time required for a rack 12 to go through a complete loading and unloading cycle, or in other words, referring to FIGURE 1, to move from the position shown occupied by rack 121 to the position shown occupied by rack 12a.

In order to provide for controlled intermittent movement of the racks in their travel from the position shown occupied by rack 12z to the position shown occupied by rack 12a, the timing drum 181 is provided on its periphery with a plurality of circumferentially spaced knobs 23k through 28k, FIGURE 12, there being one knob for each shelf or" a rack. For convenience in co-relating the functioning of the timing drum 181 with the racks, the knobs of the timing drum 131 have been given the same numbers as the shelves of the racks with the suifix k added. The knobs 23k to 28k are spaced apart circumferentially of the drum 181 equal distances proportional to the spacing between the shelves 23 to 28 of the racks. The distance between knob Zak and knob 23/: is greater than the distance between the other knobs, since this greater spacing represents and is proportional to the distance traveled by a rack after its last shelf has been loaded, or in other Words, the distance a rack travels from the position shown occupied by rack 12a to the position shown occupied by rack 1212.

With the above explanation of the timing drum 181, the description of the operational sequence of events will now be continued, with particular reference to FIGURES 1, 3, 12 and 15. With the elevating means 16 operating, thereby moving rack 12a from the position shown in FIGURES 1 and 3, by reason of engagement of lug 43 with the rack stub shaft 31, knob 28k of timing drum 181, FIGURE 12, moves oi'l limit switch LS1. At this time, rack 122 remains in the position shown in FIG- URES 1 and 3, since lug 47 of the elevating chain 4 1 is not yet in engagement with the stub shaft 31 of rack 12z. \Vhen knob 28k moves 01f limit switch LS1, its

contact LSl-Cl closes and its contact LS1-C2 opens,

FIGURE 15. Closing of contact LS1C1 completes a circuit to and energizes control relay CR1, thereby causing its normally open contacts CRll-Cl and CRZi-CZ to close and to complete a circuit to and energize control relay CR2. Energization of control relay CR2 effects closing of its' normally open contacts CR2-C1 and CR2-C4 and opening of its normally closed contacts CR2C2 and CR2-C3.

Opening of contact CR2C3, with contact CR4C2 being open at this time, interrupts the circuit to and deenergizes control relay CR6. De-energization of control relay CR6 effects re-opening of its contacts, CRd-CZ and CR6-C3, and re-closing or" its contacts CRfi-Cl and CR6- C4.

Closing of contact CR2-C4 energizes control relay CR7, which effects opening of normally closed contact CR7-C1, insuring against operation of nack advancing conveyor 1511 while the rack elevating means 16 is operating. Energization of control relay CR7 also effects closing of normally open contact CR7-CZ to retain control relay CR7 energized upon subsequent re-opening of contact CR2-C4.

As the rack 12a approaches the position shown occupied by rack 12b, it pushes rack 12b and consequently all the racks on run 13 ahead. At the same time lug 47 has moved around in position to engage rack 121, so that when rack 12a reaches the position shown occupied by rack 12b, rack 12z will have been moved upward one shelf space. In other words, the top shelf of rack 121 14 will register with infeed conveyor 18, and the second shelf will register with discharge conveyor 24?. 'At this instant, knob 23k will engage limit switch LS1, causing its contact LS1-C1 to re-open and its contact LSl-CZ .to reclose.

Re-opening of contact LS1-C1 de-energizes control relay CR1, whereupon its contacts CR1-C1 and CRl-CZ re-open, but control relay CR2 remains energized through closed contact CR2-C1. Re-opening of contacts CR1- C1 and CR1-C2 breaks the circuit to motor starter M1 ST, whereupon the elevating means 16 stops with rack 12a moved to the position shown occupied by rack 12b, and with rack 12z moved up with its top shelf in register with the infeed conveyor 18 and its second shelf in register with the discharge conveyor 20.

De-energization of motor starter M1ST effects reclosing of its contact MlfiT-CL It also effects re-opening of its contact M1-STC2 to de-energize control relay CR7, whereupon contact CR7-C1 re-closes and contact CR7-C2 re-opens.

During the operation of the elevating means 16, the infeed and discharge conveyors 18 and 29 have also been operating as above set forth, and they continue operating after the elevating means 16 stops, since a circuit to the infeed and discharge conveyor motor stanter M3-ST remains complete through contacts CRd-Cfi and CR3 C2, which at this time are ciosed. When the infeed and discharge conveyors 18 and 29 have operated through a distance sufiicient to introduce a row of hot loaves into the cooler and to discharge a row of cooled loaves from the cooler, the disc 177 completes one revolution, as pre-,

viously described. At this time, the lug 186, FIGURE 14, on disc 177' again engages limit switch LS3, whereupon its contact LS3-C1 re closes and its contact LS3-C2 re-opens. When LS3-C2 re-opens breaking the circuit to and de-energizing control relay CR3, contacts CRS-Cl and CR3-C2 re-open, whereupon the circuit to infeed and discharge conveyor motor starter M3-ST is broken and the infeedand discharge conveyors 18 and 211 stop. De-energization of motor starter M3-ST efiects re-olosing of its contact M3-ST-C1.

The apparatus now remains in status quo until the timer T runs out, at which time it momentarily opens switch TS- 1 and momentarily closes switch T52. The circuit to the loading and unloading pusher motor starter MZ-ST is thereupon completed and the pushers start to move. Movement of loading pusher from engagement with limit switch LS2 opens its contact LS2C1, thereby breaking the circuit to control relays CR2 and CR4. De-energization of control relay CR2 re-opens its contacts CR2-C1 and CR2C4 and re-closes its contacts CR2-C2 and CR2- CS. De-energization of control relay CR4 re-opens its contact CR4-C3 and re-closes its contacts CR l-Cl and CR4-C2.

Another cycle of events now occurs and is repeated for each shelf of rack 12z, however, during that cycle when the bottom shelf of rack 12z moves from registration with discharge conveyor 2% into registration with infeed conveyor 18, the succeeding rack, rack 12y, is moved from the position shown in FIGURE 1 to a position beneath rack 122 and with its top shelf in registration with dis charge conveyor 23.

To accomplish this, referring particularly to FIGURES 1, 12, 13 and 15, the timing drum 181 is provided on its periphery, at one side of circumferential row of knobs 23k-28k, with a shoe 203. The shoe 2113 is so disposed that it will engage limit switch LS5 when limit switch LS1 is engaged by knob 27k, corresponding to the position of I rack 12x whenit has been intermittently elevated to bring its bottom shelf in registration with discharge conveyor 15 broken so that the rack advance conveyor 150 does not start.

After the pushers 19 and 21 have now simultaneously loaded and unloaded the last two shelves of rack 12z, the motor starter M1-ST is energized to operate elevator motor M1, all as previously explained. Motor starter contact Ml-ST-CZ thereupon closes and completes the circuit to rack advance conveyor motor starter M4-ST to start operating the rack advance conveyor 150. When the rack advance conveyor 150 operates, the timer disc 187 rotates, as previously explained, whereupon limit switch LS4 is released from engagement by disc shoe 2&4, thereby effecting closing of contact LS4-C2 to maintain rack advance motor starter M4ST energized, so that rack advance conveyor 150 continues to operate when the shoe 203 of drum 181 rides oif limit switch LS5 to elfect re-opening of its contact LS5-C1. At the same time that contact LS4-C2 closes, the contact LS4-C1 of limit switchLS4 opens to insure against operation of loading and unloading pushers 19 and 21 while the rack advance conveyor 150 is openating.

It will be recalled, at this stage in the operation of the cooler, rack 12a has been movedby the elevating means 16 to the position shown occupied by rack 12b, thereby pushing all the racks in the upper run 13 ahead one rack space. Simultaneously, the lowering means 32 has moved rack 1212 forwardly to push the racks in lower run 14 forward, so that rack 12y is in position to be engaged by lug 155 upon operation of the rack advance conveyor 150. The relation of the elements is such, so that when lug 155 has moved from its position shown in FIGURE 1 to a position shown occupied by lug 156, thereby moving rack 12y to the position shown occupied by rack Hz, the timer disc 187 will have rotated through one half a revolution so that its shoe 205 will now engage limit switch LS4. This will restore contact LS4-C1 to closed position and contact LS4-C2 to open position. Re-opening of contact LS4-C2 breaks the circuit to motor starter M l-ST, thereby stopping the rack advance conveyor 1150. Upon reaching the aforesaid position, the top shelf of rack 12y is in alignment with discharge conveyor 20, in which position the top shelf engages limit switch LS7 to hold its normally open contact LS7-C1 closed. Thus the loading and unloading pushers can not function unless a rack has been engaged by the rack advance conveyor 159 and been moved to a position aligning its top shelf with the discharge conveyor 29. As rack 12y is advanced by rack advance conveyor 150 to the position shown occupied by nack 12z, as described above, rack 12z will be raised by the elevating means 16 to the position shown occupied by rack 12a, at which time knob 28k, corresponding to a bottom rack shelf, will engage limit switch LSl to stop the elevating means 16 as previously described. A new cycle of events is now ready to occur.

While the invention has been described with particular reference to a bread cooler, it is apparent that it may also have other applications, as for example, in a rack type proofer wherein pans of dough to be proofed are conveyed through the housing 10. Room air may be circulated through the housing by fans 223, or air condi tioned with respect to temperature or humidity maybe circulated through the housing 10. a

This is a continuation of my copending application Serial No. 27,690, filed May 9, 1960 and now abandoned.

I claim:

1. In an'apparatus of the character described, means for conducting a succession of racks, having a plurality of superimposed equidistantly spaced shelves, in a closed loop, said means including upper and lower longitudinally extending track means for supporting on each row of contiguous racks and an elevating conveyor at one end of said track means having rack engaging elements for raising successive racks to said upper track Ins/fins, means for intermittently operating said elevating i5 conveyor to move a rack vertically a shelf space at a time, means adjacent said elevating conveyor for unloading articles from successive rack shelves and for loading articles on successive rack shelves, said last named means including a lower support for articles to be unloaded from said rack shelves disposed in a plane above the plane of the top shelf of a rack on said'lower track means and an upper support for articles to be loaded onto said rack shelves disposed a shelf space above said lower support, and also including pusher means for slidably moving articles onto said lower support from an alined rack shelf and for slidably moving articles from said upper support onto an alined rack shelf, an endless rack advancing conveyor at the end portion of said lower track means adjacent said elevating conveyor having rackengaging means for advancing and raising a rack into position to be engagedby said elevating conveyor, and control means for operating said rack advancing conveyor to move a rack to a position aligning its top shelf with said lower support as a preceding nack is elevated by said elevating conveyor from a position in which its bottom shelf is aligned with said lower support to a position in which its bottom shelf is aligned with said upper support.

2. An apparatus as set forth in claim 1 in which said control means includes means operated by said elevating conveyor for initiating operation of said rack advancing conveyor and means responsive to a predetermined travel of said rack advancing conveyor for interrupting operation thereof.

3'. An apparatus as set forth in claim 1 includingmeans for simultaneously operating said pusher means for simultaneous loading and unloading two shelves of the sameor different racks.

4. In an apparatus of the character described, means for conducting a succession of racks, having a plurality of superimposed equidistantly spaced shelves, in a closed loop, said means including upper and lower longitudinally extending track means for supporting on each a row of contiguous racks and an elevating conveyor at one end of said track means having rack engaging means for raising successive racks to said upper track means; means for intermittently operating said elevating conveyor to move a rack vertically a shelf space at a time, an unloading conveyor disposed adjacent said elevating conveyorand a loading conveyor disposed a shelf space above said unloading conveyor, 21 rack advancing conveyor extending along said lower track means adjacent said elevating conveyor engageable with successive racks for moving them along said lower track means and upwardly therefrom into vertical alinement with said elevating conveyor, a motor for said rack advancing conveyor, control means synchronized with movement of said elevating conveyor for initiating operation of said rack advancing conveyor motor in coincidence with movement of a rack by said elevating conveyor from a position in which the bottom shelf of said last named rack is alined with said unloading conveyor, means responsive to movement of said rack advancing conveyor through a distance bringing the top shelf of a following rack in alinement with said unloading conveyor for stopping said rackadvancing conveyor rnotor, said rack advancing conveyor operating at a speed to convey said following rack to said last named position prior to elevation of the preceding rack from a position in which its bottom shelf is alined with said loading conveyor, pusher means associated with each of said loading and unloading conveyors, and means for simultaneously operating said pusher meansto simultaneously load and unload both two successive shelves of a rack as well as the bottom and top shelves of two successive racks.

5. In an apparatus of the character described, means for conducting a succession of racks, having a plurality of superimposed equidistantly spaced shelves, in a closed loop including upper horizontal track' means and lower horizontal trackmeans for supporting on each a row of contiguous racks movable therealong, endless conveying means at one end of said track means including a vertical run and an upper horizontal run, said conveying means having means engageable with a rack for elevating it along said vertical run to said upper tracks and along said horizontal run for moving it along said upper tracks out of the vertical path of a succeeding rack, means for intermittently operating said conveying means for raising a rack along said vertical run in steps equal to the spacing between the rack shelves and then through a longer step to move said rack along said upper track, a rack advancing conveyor for moving a second rack along'said lower track into position beneath said first rack for engagement by the rack engaging means of said first conveying means, means for intermittently operating said rack advancing conveyor including timing means for operating said rack advancing conveyor while said first named conveying means is raising said first rack through its final shelf space and means for interrupting operation of said rack advancing conveyor to stop said second rack a shelf space below said first rack, and the rack engaging means of said first conveying means being arranged to engage said rack during the final portion of the longer step of said first conveying means to raise said second rack one shelf space.

6. In an apparatus of the character described, means for conducting a succession of racks in a closed loop including upper and lower horizontal track means for supporting on each a row of contiguous racks movable therealong, a first endless conveyor at one end of said upper and lower track means including a vertical run and an upper horizontal run; said racks having a plurality of equidistantly vertically spaced shelves; equidistantly spaced means carried by said endless conveyor for engaging successive racks, said rack engaging means being spaced a distance apart exceeding the distance between the top and bottom shelves of a rack plus one additional shelf space; operating means for said first endless con veyor including means for cyclically moving successive rack engaging means along said vertical run a shelf space at a time equal to one less than the number of shelves of a rack and then a horizontal distance exceeding a shelf space, whereby to elevate a rack a shelf space at a time to the upper end of the said vertical run and to then convey it a horizontal distance onto said upper track sufiicient to clear a succeeding rack in said vertical run; a second endless conveyor adjacent the lower end of said vertical run having rack engaging means; means for intermittently operating said second endless conveyor including means for initiating operation thereof to move a succeeding rack along said lower track means beneath a preceding rack on said elevator while said preceding rack is being elevated through its final shelf space in said vertical run and for interrupting operation of said second endless conveyor when said last named succeeding rack reaches a position one shelf space below said preceding rack in position to be picked up by a rack engaging means or" said first endless conveyor.

7. in rack circulating apparatus; means for conducting a succession of racks having a plurality of superimposed equidistantly spaced shelves in a closed loop; said means including upper and lower longitudinally extending track means for supporting on each a row of contiguous racks, and an elevating conveyor at one end of said track means having rack engaging means for raising successive racks to said upper track means; means adjacent said elevating conveyor for unloading articles from successive rack erally longitudinally extending portion and a generally vertically extending portion so that said rack advancing conveyor longitudinally advances and raises a rack into position to be engaged by said elevating conveyor; and means for moving said rack advancing conveyor at a greater rate of speed than said elevating conveyor, the rack advancing conveyor operating to move a rack longitudinally and vertically to a position substantially alining its top shelf with said lower support as a preceding rack is elevated by said elevating conveyor from a position in which its bottom shelf is substantially alined with said lower support to a position in which its bottom shelf is substantially alined with said upper support.

8. In rack circulating apparatus; means for conducting a succession of racks having a plurality of superimposed equidistantly spaced shelves in a closed loop; said means including upper and lower longitudinally extending track means for supporting on each a row of contiguous racks, and an elevating conveyor at one end of said track means having rack engaging means for raising successive racks to said upper track means; means adjacent said elevating conveyor for unloading articles from successive rack shelves and for loading articles on successive rack shelves, said last named means including a lower support for articles to be unloaded from said rack shelves and an upper support a shelf space thereabove for articles to be loaded on to said rack shelves, and also including pusher means for moving articles onto said lower support from an alined rack shelf and for moving articles from said upper support onto an alined rack shelf; a rack advancing conveyor at the end portion of said lower track means adjacent said elevating conveyor having rack engaging means, said conveyor having a generally longitudinally extending portion and a generally vertically extending portion so that said rack advancing conveyor longitudinally advances and raises a rack into position to be engaged by said elevating conveyor; and means for moving said rack advancing conveyor at a greater rate of speed than said elevating conveyor, the rack advancing conveyor operating to move a rack longitudinally and vertically to a position in which its top shelf is spaced only a shelf space from the bottom shelf of the preceding rack.

9. In rack circulating apparatus: means for conducting a succession of racks having a plurality of superimposed equidistantly spaced shelves in a closed loop; said means including upper and lower longitudinally extending track means for supporting on each a row of contiguous racks, and an elevating conveyor at one end of said track means having rack engaging means for raising successive racks substantially to said upper track means; means adjacent said elevating conveyor for unloading articles from successive rack shelves and for loading articles on successive rack shelves, said last named means including a lower support for articles to be unloaded from said rack shelves and an upper support for. articles to be loaded onto said rack shelves, and also including pusher means for moving articles onto said lower support from a substantially alined rack shelf and for moving articles from said upper support onto a substantially alined rack shelf; a rack advancing conveyor at the end portion of said lower track means adjacent said elevating conveyor having rack engaging means, said conveyor having a generally longitudinally extending portion and a generally vertically extending portion so that said rack advancing conveyor longitudinally advances and raises a rack into position to be engaged by said elevating conveyor; and means for moving said rack advancing conveyor at a greater rate of speed than said elevating conveyor and in synchronism therewith to supply racks thereto in properly spaced relation.

10. In rack circulating apparatus: means for conducting a succession of racks having a plurality of superimposed equidistantly spaced shelves in a closed loop; said means including upper and lower longitudinally extending track means for supporting on each a row of contiguous racks, and an elevating conveyor at one end of said track means having rack engaging means for raising suc oessive racks substantially to said upper track means; means for driving said elevating conveyor; means adjacent said elevating conveyor for unloading articles from suecessive rack shelves and for loading articles on successive rack shelves, said last named means including a lower support for articles to be unloaded from said rack shelves and an upper support for articles to be loaded onto said rack shelves, and also including pusher means for moving articles onto said lower support from a substantially alined rack shelf and for moving articles from said upper support onto a substantially alined'rack shelf; rack advancing conveyor means at theend'portion of said lower track means adjacent saidelevating conveyor and having rack engaging means, said rack advancing conveyor means having a generally vertically moving portion so that said rack advancing conveyor means raises a rack above said lower track means into position to be engaged by'said elevating conveyor; and means for moving said rack advancing conveyor means to raise a rack at a greater rate of speed than said elevating conveyor rises and in synchronism therewith to supply racks thereto in properly spaced relation.

References Cited in the file of this patent UNITED STATES PATENTS 2,823,311 Temple Feb. 18, 1958 

1. IN AN APPARATUS OF THE CHARACTER DESCRIBED, MEANS FOR CONDUCTING A SUCCESSION OF RACKS, HAVING A PLURALITY OF SUPERIMPOSED EQUIDISTANTLY SPACED SHELVES, IN A CLOSED LOOP, SAID MEANS INCLUDING UPPER AND LOWER LONGITUDINALLY EXTENDING TRACK MEANS FOR SUPPORTING ON EACH ROW OF CONTIGUOUS RACKS AND AN ELEVATING CONVEYOR AT ONE END OF SAID TRACK MEANS HAVING RACK ENGAGING ELEMENTS FOR RAISING SUCCESSIVE RACKS TO SAID UPPER TRACK MEANS, MEANS FOR INTERMITTENTLY OPERATING SAID ELEVATING CONVEYOR TO MOVE A RACK VERTICALLY A SHELF SPACE AT A TIME, MEANS ADJACENT SAID ELEVATING CONVEYOR FOR UNLOADING ARTICLES FROM SUCCESSIVE RACK SHELVES AND FOR LOADING ARTICLES ON SUCCESSIVE RACK SHELVES, SAID LAST NAMED MEANS INCLUDING A LOWER SUPPORT FOR ARTICLES TO BE UNLOADED FROM SAID RACK SHELVES DISPOSED IN A PLANE ABOVE THE PLANE OF THE TOP SHELF OF A RACK ON SAID LOWER TRACK MEANS AND AND UPPER SUPPORT FOR ARTICLES TO BE LOADED ONTO SAID RACK SHELVES DISPOSED A SHELF SPACE ABOVE SAID LOWER SUPPORT, AND ALSO INCLUDING PUSHER MEANS FOR SLIDABLY MOVING ARTICLES ONTO SAID LOWER SUPPORT FROM AN ALINED RACK SHELF AND FOR SLIDABLY MOVING ARTICLES FROM SAID UPPER SUPPORT ONTO AN ALINED RACK SHELF, AN ENDLESS RACK ADVANCING CONVEYOR AT THE END PORTION OF SAID LOWER TRACK MEANS ADJACENT SAID ELEVATING CONVEYOR HAVING RACK ENGAGING MEANS FOR ADVANCING AND RAISING A RACK INTO POSITION TO BE ENGAGED BY SAID ELEVATING CONVEYOR, AND CONTROL MEANS FOR OPERATING SAID RACK ADVANCING CONVEYOR TO MOVE A RACK TO A POSITION ALIGNING ITS TOP SHELF WITH SAID LOWER SUPPORT AS A PRECEDING RACK IS ELEVATED BY SAID ELEVATING CONVEYOR FROM A POSITION IN WHICH ITS BOTTOM SHELF IS ALIGNED WITH SAID LOWER SUPPORT TO A POSITION IN WHICH ITS BOTTOM SHELF IS ALIGNED WITH SAID UPPER SUPPORT. 